Heatwave-driven power demand surge triggers localised outages across cities

As temperatures soar and electricity demand touches record highs, cities across India are witnessing frequent outages driven by ageing infrastructure and transmission constraints

As temperatures soar and power demand hits record highs, power outages are becoming increasingly frequent across the country. Gurugram saw one of the worst disruptions in recent days. On Friday (May 22), a fire broke out at a 220-kV transformer substation, disrupting electricity supply in several parts of the city, as per reports. It also halted Rapid Metro services for a while, leaving passengers stranded during their commute, with some of them forced to disembark and walk along the tracks. 

“It is horrible,” said a Gurugram resident, describing the worsening power situation in the city. She said electricity outages lasting 1–2 hours in the evening have become common. “It has increased in the recent past,” she said, adding that even when the supply is not cut off completely, low voltage makes it hard to run heavy appliances such as air conditioners and refrigerators.

 

Her experience is among many emerging from across the Delhi-NCR region. A resident of Faridabad said power cuts lasting more than an hour every day have become frequent in the past week. “On some days, power was cut for two hours,” she said. On Saturday, there was a power cut of about 30 minutes in the afternoon, followed by another cut of one hour in the late afternoon (4:30 pm to 5:30 pm), she added.

 

Cities in West Bengal such as Bangaon have witnessed 2–3 hours of power cuts in the past one week. Prayagraj in Uttar Pradesh is another city where power cuts are frequent. There are reports of outages in many parts of the country, including Chennai and other metro cities. While Grid India data show negligible shortages, the real outages tell a different story. On May 21, it reported a 2.57-GW non-solar shortfall, constituting only 1 per cent of the total demand, which peaked on Thursday at 270.82 GW, after breaking records each day in the three days before.

 

This is because adequacy is measured at the state boundary, not at the household level, said Rohit Vijay, associate fellow, Centre for Social and Economic Progress (CSEP). “After power reaches the state boundary, it passes through the state transmission utility and then the discoms before reaching consumers. While the system may appear adequate there, it does not reflect the actual shortages consumers face,” he said.

 

However, the reasons for such power cuts are many, ranging from old distribution infrastructure and high spot market power prices to transmission bottlenecks and system stress on thermal power plants.

 

The ageing infrastructure of many distribution companies (discoms) cannot handle high temperatures and peak demand simultaneously. “Perhaps the biggest issue is at the local grid level. Many transformers, feeders and transmission lines are old and heavily overloaded. During heatwaves and peak summer demand, transformers fail and feeders trip, causing local outages even when power is available in the system,” said Vibhuti Garg, director, South Asia, IEEFA.

 

In Delhi’s Janakpuri area, near Uttam Nagar East, there were power cuts for more than four hours on consecutive nights on May 20 and 21, Vijay said. “Private discoms may have enough contracted generation, but the infrastructure in metro cities was designed many years ago and is not capable of handling current temperatures and demand levels,” he said.

 

Even when discoms forecast higher demand, in many cases they resort to load shedding instead of buying expensive spot power, Vijay said, adding that some of this can be presented as legally permissible by citing infrastructure constraints or maintenance needs.

 

Transmission constraints are also one of the major reasons for causing outages. At the national level, there may be adequate power generation capacity, but power cannot always be transmitted to where it is needed. “In several states, transmission constraints and inadequate evacuation infrastructure prevent surplus power from reaching deficit regions,” said Garg.

 

Demand forecast underestimation is another culprit. While official projections assume demand growth of around 6 per cent, actual growth is closer to 9 per cent, Vijay said. “Power purchase agreements signed by discoms are based on lower growth assumptions, leaving a gap in planning,” he added.

 

The National Load Despatch Centre’s (NLDC’s) Short-Term National Resource Adequacy Plan projected 15–20 GW of unserved demand in May 2026, while PSP reports showed only up to 2.57 GW of shortfall. “This suggests there may be a significant gap between actual shortages and officially reported figures, possibly due to unreported distribution-level load shedding,” he said.

 

Moreover, stress on thermal plants to ramp power supply up and down based on renewable energy availability is also causing forced outages, Vijay noted. “For efficient plants, minimum plant load factor (PLF) is manageable, but for older state plants it is a significant issue,” he said. Thermal plants have to run at minimum levels of up to 55 per cent PLF during the day when solar generation is high, but then ramp up sharply in the evening when solar generation falls.

 

“According to Central Electricity Authority data, around 83 per cent of the thermal generation shortages were forced — that is, unplanned technical failures — rather than scheduled maintenance. High ambient temperatures are contributing to failures by placing additional stress on ageing equipment,” Vijay said.

 

Grid India data show 36.2 GW of generation capacity was offline on May 22, primarily due to forced outages caused by equipment failures, he added. “High temperatures accelerated mechanical stress on older thermal units, contributing to unplanned breakdowns,” he said.

 

Experts suggest demand response mechanisms and the implementation of time-of-day (TOD) tariffs as a solution to incentivise consumers to shift consumption towards daytime when solar power is abundant. Rapid storage deployment, compensation for flexible operations for coal plants, upgradation of distribution infrastructure, and long-term planning considering actual system conditions during peak hours are required to avoid outages going forward.